Reference no: EM134625

Question1

A 27 kg chair initially at rest on a horizontal floor requires a 377 N horizontal force to set it in motion. Once chair is in motion, a 351 N horizontal force keeps it moving at a constant velocity.

The acceleration of gravity is 9.81 m/s2.

What is coefficient of static friction between chair and floor?

Question2

A person driving her car at 51 km/h approaches an intersection just as traffic light turns yellow. She knows that a yellow light lasts only 2.0 s before turning to red, and she is 30 m away from the near side of the intersection. The intersection is 15 m wide. Her car's greatest deceleration is -6.6 m/s2, whereas it can accelerate from 51 km/h to 70 km/h in 5.7 s. Overlook lengths of her car and her reaction time.